#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include <list>
class T1
{
public:
	int type;
	int b;
};

class T2
{
public:
	int type;
	int b;
	int c;
};

int main()
{
	std::list<int> a;
	a.push_back(1);
	auto begin = a.begin();
	a.erase(begin);
	int s = a.size();
	return 0;
}